“A History of the California Interscholastic Federation” by William W. Russell, the CIF’s official history, says there were four (not three sections) in the beginning. I’ve also enclosed the text of my introduction to Bay Area Sports Stars, which explains the Bay Area situation in a bit more detail.
Anyway, here are the starting dates for the sections of the CIF, which was formed in March, 1914:
North Coast, 1914 (originally called Bay)
Los Angeles, 1935
Sacramento-San Joaquin, 1944
San Francisco, 1945
San Diego, 1959
Central Coast, 1965
Here’s the John Spalding version of the local situation
A Brief History Of High School Sports
High school athletes have been competing against one another in the nine counties of the San Francisco Bay Area since the late 19th Century. Football was governed in 1891 by the Amateur Academic Athletic Association. Other games and meets were arranged in a haphazard manner until 1894, when competition around the bay was provided by the Academic Athletic League.
The AAL provided structured competition for boys in football, baseball, swimming, tennis and track and field. Basketball was added early in the 20th Century. A few schools offered less formal interscholastic competition for girls in baseball, basketball, swimming, tennis and volleyball.
Teams represented schools, but were not under the direct control of principals, superintendents or elected school officials. There were frequent disagreements over eligibility, rules and finances.
In July, 1913, a California School Teachers Association committee recommended school officials adopt policies to control interscholastic athletics, which effectively meant boys sports. After a series of meetings, the California Interscholastic Federation was formed in March, 1914. Its main purpose was to put the direction of high school athletics in the hands of educators.
The CIF was divided into four geographical sections which mirrored those of the California Teachers Association. One of the divisions was the Bay Section — later renamed the North Coast Section — which stretched from the Oregon border to King City (King City is a city in Monterey County) and included Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Solano and Sonoma counties.
The NCS was established in September, 1914. Of 70 high schools invited to join, only 15 responded initially. Some needed more time to meet and discuss the new organization. Original NCS members included Alameda, Antioch, Berkeley, Cloverdale, Fremont, Healdsburg, Los Gatos, Oakland, Oakland Technical and Richmond High Schools. Scores of other schools became members within the next few years.
My notes: I believe these are the missing five from above.
San Jose, Berkeley, Santa Rosa, Palo Alto, Mountain View
Because the number of high schools had grown so large as a result of the post-World War II population boom, the North Coast Section was divided in 1965, creating a new Central Coast Section with jurisdiction over schools in San Mateo, Santa Clara, Santa Cruz, San Benito and Monterey counties.
Schools in all five sections belong to leagues which sponsor competition in up to 16 sports for boys and girls — who became full fledged partners in the prep sports world when federal Title IX legislation was passed in the early 1970s.
Many athletes compete for post season section championships. In addition, statewide titles are awarded by the CIF in track and field (starting in 1915 for boys and 1974 for girls), boys wrestling (1973), girls volleyball (1978), basketball (1981), cross country (1988), girls golf (2003) and boys golf (2004).
When the California Interscholastic Federation was founded in 1914, one of the four sections created was the Bay Section. Since it stretched from King City to the Oregon border, it was quickly renamed the North Coast Section. Some Solano County schools moved to the Sac-Joaquin Section after it formed in 1942. By 1965, the NCS had grown so large that the territory from King City north to the San Mateo-San Francisco County line was removed from the NCS to create a new Central Coast Section, which held its first track and field competition in 1966.